Rotary boring head having radially adjustable cutting arms



1956 E. ANDERSON EI'AL 7 ROTARY BORING HEAD HAVING RADIALLY ADJUSTABLE CUTTING ARMS Filed Jan. 4, 1956 2 SheetsI-Sheet 1 Fig.4 r INVENTOR.

EDWARD 1.. ANDERSON ISY BY EMILJHLNK Dec. 4, 1956 E. L. ANDERSON EI'AL ROTARY BORING HEAD HAVING RADIALLY ADJUSTABLE CUTTING ARMS 2 Sheets-Sheet 2 Filed Jan. 4, 1956 INVENTOR. EDWARD L. ANDERSON EMI L J. HLINSKY ATTORNEY United States Patent ROTARY BORING HEAD HAVING RADIALLY ADJUSTABLE CUTTING ARMS Edward L. Anderson, and Emil J. Hlinsky, Chicago, Ill.,

assignors to Goodman Manufacturing Company, Chi- This invention relates to improvements in boring heads for mining machines of the type in which one or more boring heads are rotatable on .a horizontal axis in advance of the machine, each boring head consisting of a rotatable hub having a plurality of radially extending arms on which are mounted forwardly projecting cutter supports. Boring heads of this general character usually include means for collapsing or retracting the outer ends of the arms to facilitate withdrawal of the head from the bore, and also to facilitate the transporting or tramming of the mining machine from place to place in the mine. One of the arrangements for retracting the ends of the arms has been to provide a telescopic end portion on each arm.

The principal object of the present invention is to provide a simple and eflicient boring head structure, having telescopic end portions at the outer end of the arms.

A further object of the invention is to provide an arm structure of the character above described, wherein the telescopic end portions have splined engagement with the hub portion to provide desired stability against the enormous twisting stresses imposed upon the end portions while cutting.

The invention may best be understood by reference to I the accompanying drawings in which:

. Figure l is a fragmentary cross-section of a-cutter head constructed in accordance with the invention, with theend of one of the radial arms broken away.

Figure 2 is a fragmentary front view of the cutter head structure shown in Figure 1, but with the cutter support removed from the telescopic end portion of the arm.

Figure 3 is a top plan view of the telescopic end portionshown in Figure 2. j r

Figure 4 is a detailed section taken on line 4 of Figure 1.

Referring now to details of the embodiment of the invention shown in the drawings, indicates a main hearing for the honing head indicated generally at 11. The bearing 10 forms part of the supporting frame of a mobile mining machine. The boring head 11 consists of a hub 12 fixed on a hollow drive shaft 13, as by key 13. The hub is joumalled in the main bearing 10, and has a plurality of hollow radially extending inner arm portions 14, 14 formed integrally therewith, and in diametrical alignment with each other.

The two inner arm portions 14 have a smooth bore 15 opening to their outer ends, which bore also continues through the hub portion. The inner end portions 14 are cylindrical in crosssection with the bore 15 concentric therewith, as shown in Figure 4, for simplicity and economy in manufacture.

A telescopic outer end portion, indicated generally at 16, is mounted on the end of each inner end portion, said outer end portion consisting of a hollow housing 17,

2,772,870 Patented Dec. 4, 1956 "ice 2 having a cylindrical end portion 18 which fits into the bore 15 for slidable engagement therein. The end portion 18 has an annular groove 18* thereabout, for receiving a conventionalsealing member such as a ring, therein. The housing 17 also has a forwardly extending portion 19 at its upper end, which has a widened trout face 20 adapted to support a forwardly projecting cutter bracket 21 (see [Figure 'l) which may be of conventional form, having a plurality of bit clusters 22 along its forward edge for cutting a kerf in the working face of the mine.

The end portion 19 of the housing 17 has an integrally formed plow plate 23, of the kind commonly employed with boring heads of this type for the purpose of sweeping the cuttings deposited upon the mine floor into position to be collected by the conventional conveyor (not shown) of the mining machine. As will be seen from Figures 1 and 3, the plow plate 23 extends inwardly from the outer end of the housing 17 and partially overlaps the inner arm portion 14 in various positions of longitudinal adjustment of the telescopic end portion 16, as will now be described.

The housing 17 has a hollow sleeve 24 disposed concentrically therein, the upper end of said sleeve extending into a bore 25 at the upper end of said housing and secured to a plate 26 recessed in the upper end of said housing and secured to the latter by bolts 27 (see Figures 1 and 3). The inner end of the sleeve 24 has a threaded portion 28 to which a screw member 29 is connected. The outer end of said screw member terminates near the outer end of the inner arm portion 14. The inner end of the screw member 29 is journalled in a bushing 30 adjacent the hub axis, which bushing is fixed, as by welding 31, to an annular hollow anchor collar 32, which fits into the bore 1'5 and also supports a duplicate bushing 30 at its lower end, for the screw member 29 of the opposite arm of the boring head, as will presently be more fully described.

The collar 32 has a cross-bore 33, the rear end of which is adapted to fit over an annular plug '34, fitting in a bore 35 formed in anpintermediate transverse wall 12 of the hub 12. The bores '33 and 35 and the plug 34 are all disposed concentrically with the axis of the head. The plug 34 is secured in the hub by bolts 36, 36 passing through the plug 34 from its front face, and threadedly engaged with the front end of the shaft 13 which projects into the rear end of the hub. f

The bushing 30 has a hollow sleeve 88 secured at its inner end as by welding 39. The outer surface of sleeve 38 is provided with longitudinal splines 39 engaging splines 40 formed in the inner face of the cylindrical end portion 18 of housing 17. As will be seen from Figure 1, splined sleeve 38 has ample clearance around the screw member 29 and the threaded sleeve 24 of the telescopic end portion 16, to permit the latter end portion to be telescopically adjusted toward and away from the hub by rotation of the screw member 29.

To effect telescopic adjustment of the end portion '16 the inner end of the screw member 2'9 has a bevel gear 42 suitably fixed thereon below the' bushing '30. The bevel gear 42 is meshed with a bevel gear 43 mixed to the front end of a controlshaft 44 extending concentrically through the drive shaft 13 and the plug '34 fixed in the intermediate wall of the hub 12 as previously described.

It will be observed from Figure 1 thatthe lower arm of the boring head assembly has a duplicate mechanism for effecting telescopic adjustment of an end portion (not shown) similar to the end portion 16, as previously described.

The outer end of hub 12 has an axially extending bore 45 of slightly larger diameter than the cross bore 33 in the anchor collar 32. The outer end of the bore 45 is closed'by suitable means such as a' sealing cap 46.

Lubricating ducts 47, 47 provide communication betwe the. ross borc 33 of col ar 3 and th spa es suround ng th pl n d. s e .8 within th bo e "l o both inner' rm Po ions 1 to a l a ujb i a ion ffl h p ined u iac 0- t c u r a n ducts .48. Pa s ough th o bu g 1 t pro de. om munication from within the collar 32 to the spaces surrounding the screw members 23, 29 within the splined sleeve .38, .to insure lubricationof the outer ends the Said screw members and the hollow sleeves 24 in which they are threaded.

.The structure above described is especially adapted for easy assembly of its principal parts in the'foljlowins, m nnerz p With the control shaft 44 partially withdrawn to the rear, and with the hub assembled on drive shaft 13, the splinedsleeves 38 and the sleeve 32 in assembled relation is bodily inserted in either'end opening of the bores to thecentral position relative to the axis of the hub. With sealing cap 46 removed, access is afforded through the bore 515 in the hub and the cross-bore 33 in the .col-

lar 32 so as to permit the plug 34 to be inserted in bore 35. The plug 34 is then secured to the front of the drive shaft 13 by bolts 36, with a portion of said plug projecting into the cross-bore 33 at the adjacent side of the collar 32. This will anchor the splined sleeves 33 against rotation in the bore 15, and also from endwise movement in said bore. The control shaft 44 is then projected into its normal position shown in Figure l, and the bevel gear 43 is secured to the end of said control shaft. The telescopic end portions 16 of the arms are then mounted on their respective arms, with the sleeves '24, and their threaded screw members, assembled thereon, are inserted in the outer ends of bore 15 with the threaded shafts in extended position so that their inner ends pass through the bearing bushings 30. The bevel The use and operation of the structure will be manitest from the above description. The telescopic end portions 16, 16 may be simultaneously adjusted toward .or away from the axis of rotation of the head by rotating gears 42, 42 are then fixed on the inner ends of the i i thecontrol shaft 44 by any suitable means disposed at H the rear end ofthe drive shaft 13. h g

The telescopic end portions are restrained from r0- tationin the cylindrical inner end portions 14 by the splines 39, 40. The entire assembly provides an es p'ecially simple sealed structure for its simple and effective intended purpose. i l Although we have shown and described certain embodimentsof our invention, it will be understood that various changes and modifications may be made 'without departing from the spirit and scope of the invention as defined in the appended claims.

We claim:

1. In a rotary boring head comprising a hollow hub and a plurality of radial arms, each of said arms comprising an inner arm portion with a cutter-carrying telescopic end section at the outer end thereof, the inner arm section having a smooth bore opening to its outer end, the telescopic end section having a cylindrical inner end portion with its outer surface slidably engaged in said bore, a hollow sleeve having its inner end fixed centrally of said hub, and having its outer surface in slidable splined engagement with the inner surface of said cylindrical end portions, an inner sleeve fixed .on said telescopic end section adapted to project into said splined sleeve, 2. bushing fixed to said splined sleeve adjacent the axis of said head, a screw member having its outer end threadedly engaged in said inner sleeve, and its inner end journalled in said bushing, and means in said hub for rotating said threaded member to effect adjustment of said telescopic end section relative to said inner arm section. i

2. The structure of claim 1, wherein the splined sleeve and bushing-are fixed on an anchoring collar adapted to be slida'bly assembled in the bore and means are provided for detachably securing said collar in said bore.

3. The structure of claim 2 wherein the hub has an axially disposed opening at its front end, the anchoring collar has a transverse through-bore adapted to be aligned with the end opening in the hub, the means for detachably securing said collar in the bore consists of a plug adapted to fit in the portion of the through-bore atthe rear side of the collar and detachably secured in the hub by means accessible through the end opening in the hub and the portion of thejthrough bore at the front end of said collar, and the means for rotating the screw member includes a control shaft disposed concentrically of the hub and extending through the plug, and meshing bevel gears are fixed on the adjacent ends of thescrew member and the control shaft within said anchoring collar.

4. The structure of claim 3, wherein the radial inner arm sections are in diametric alignment with each other and their smooth bores extend continuously through the hub, and each of said arms have telescopic end structures on each arm section, including duplicate splined sleeves, screw members, bushings, and bevel gears fixed on said screw members, and the anchoring collar is common to both telescopic end structures, and is insertable, together with the splined sleeves and bushings fixed thereon, from one end of the continuous smooth.'-bore for fixing the anchoring collar centrally of the hub.

k terence Ci d n the e of this p ent UNITED STATES PATENTS 

